It depends on the situation. For instance, if a person suffering from borderline personality disorder/antisocial personality disorder is assessed to be a danger to him/herself or to an identifiable person, and if hospitalization is the least restrictive environment for treatment or it's the most appropriate treatment, s/he would be considered for hospitalization.
Sam Vaknin who is a real expert on narcissistic personality disorder needed a couple of years in jail before he realized that something in his personality differed from that of others.